The detergent industry has a number of surfactant-related needs, including effective surface-active properties. The surfactants wet surfaces, reduce surface and interfacial tensions, disperse, solubilize and emulsify. All of these may be critical to the desired performance of the final detergent product. In addition, the increased use of liquid detergents and the complexity of these formulations increase the need for compatible surfactants and other detergent ingredients. Furthermore, the detergent ingredients need to be safe with respect to human exposure and long-term environmental impact.
It has been surprisingly found that the inclusion of specially selected soap materials into liquid detergent compositions containing a lipolytic enzyme (lipase) substantially enhances their ability to rapidly lower the interfacial tension of aqueous washing liquors containing greasy and oily soils. This substantial reduction of interfacial tension of greasy and oily soils improves their removal from soiled surfaces and inhibits the redeposition of the soils onto substrates.
It has also been suprisingly found that liquid detergent compositions containing a lipolytic enzyme and a specially selected soap material provide enhanced removal of greasy/oily soils particularly when the detergent composition is used in a pre-treatment application to greasy/oily soil stains on fabrics prior to and in conjunction with a normal wash process of the fabrics.
Moreover, it has been found that certain soaps, e.g. secondary alkyl carboxyls, not only provide the desired lowering of interfacial tension, with its attendant increase in grease removal performance, but also allow the formulation of liquid detergent compositions containing a lipase which are stable and homogeneous. In addition, it has been found that liquid detergent compositions comprising the specifically selected soaps are very useful when said lipase-containing liquid detergents are in direct contact with the greasy/oily satins and/or soils on fabrics such as during pretreatment.